Question

Two cubes each of volume 27 cm³ are joined end to end to form a solid. Find the surface area of the resulting cuboid.

Answer 1

Volume of cube = 27 cm³ (given)

Let ‘a’ cm be the length of each side of the cube.

We know, volume of cube = (side)³ cubic units

⇨ 27 = a³

or a = 3 cm

When two cubes are joined cuboid is formed.

Find dimensions of cuboid:

Length = l = 2a = 2 × 3 cm = 6 cm

Breadth = b = a = 3 cm

Height = h = a = 3 cm

Now,

Surface area of cuboid = 2(lb+bh+lh)

= 2(6 × 3 + 3 × 3 + 6 × 3)

= 2(18 + 9 + 18)

= 90

Surface area of resulting cuboid is 90 cm²